The conventional means of configuring a door frame for accommodating a door bolt is to cut out a bolt indentation in the door frame to align with, receive and surround a door bolt when the door is closed and the bolt is in an extended (i.e. locked) position. As well, a larger, shallower indentation in the shape of a strike plate is cut out around and over the bolt indentation to receive a strike plate in such manner that the strike plate lies flush with the surface of the door frame and does not obstruct the closing of the door. The strike plate is conventionally secured to the doorjamb by means of screws driven into the doorjamb in a direction perpendicular to the plane defined by the strike plate.
However, a strike of the above conventional configuration, while being structurally simple, has the disadvantage of being fairly weak and is unable to withstand high lateral forces such as that which is caused when a strong force is applied against bolted door (the bolt extending through the strike plate). This is because the conventionally used means of securing the strike plate to the doorjamb namely, by way of perpendicularly directed screws, produces a restraining force which necessarily runs perpendicular (rather than in opposition) to the line of force exerted against the door upon an attempt to force open the door against the resistance of the door bolt lying within the doorjamb and strike plate. Moreover, the grain of the wood used to construct the doorjamb is usually such as to lie in the direction of the plane of the strike plate thereby causing a tendency of the doorjamb below the strike plate to split apart from remainder of the doorjamb when a strong force is exerted against a bolted door in an attempt to forcefully open the door.
An attempt has previously been made to provide a strike structure which overcomes the above disadvantages by using elongated strike support members which are driven horizontally through the doorjamb below the strike plate and anchored to the strike plate as taught in U.S. Pat. No. 4,453,751 which issued on June 12, 1984 to Hamilton. However, the overall configuration and installation requirements of the Hamilton strike plate support structure have been found to be unacceptable to building contractors and the like in the industry because it requires the drilling of holes in the visible outer side of the doorjamb (thereby making the installation unattractive) and complicated manoeuvring on the part of the installer to align the threaded apertures of the support member with the strike plate fasteners.
The invention herein disclosed and claimed overcomes the above disadvantages of the Hamilton strike structure and provides a strike plate reinforcing structure which is anchored to the doorjamb in a direction which opposes a force applied to a bolted door to provide greater strength to a door strike.